Download AllSync GPS User Manual

Installation and Operation Manual
AllSync® Master Clock
GPS Option
®
Part # PS000009
Rev. 3
March 2010
AllSync GPS Option
User Manual
American Time
140 3rd Street South, PO Box 707
Dassel, MN 55325-0707
Phone: 800-328-8996
Fax: 800-789-1882
american-time.com
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© American Time
AllSync GPS Option
User Manual
Table of Contents
Introduction............................................................................................................................................................4
Installation...............................................................................................................................................................5
Requirements......................................................................................................................................................5
Mounting the GPS Antenna...............................................................................................................................7
Connecting the AllSync Master...........................................................................................................................8
Configuring the AllSync Master..........................................................................................................................9
Troubleshooting....................................................................................................................................................10
Specifications.........................................................................................................................................................11
Glossary.................................................................................................................................................................12
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Introduction
AllSync GPS Option
User Manual
1.Time synchronization via the Global Positioning System - the AllSync Master can be configured to
receive timestamps from the GPS Antenna/Receiver provided with the GPS kit.
2.Automatic Time Zone Configuration via the Global Positioning System - the AllSync Master can use
the longitude position fix from the GPS Antenna/Receiver to calculate LMT - Local Mean Time. This
feature was specially designed for use by ships at sea that move through many time zones.
The Global Positioning System (GPS) is a constellation of satellites providing specially coded radio signals
that can be processed in a GPS receiver, enabling the receiver to compute position, velocity and time. The
GPS kit from American Time & Signal Co. includes such a receiver, which computes the time and transmits
this via RS-422 communication to the AllSync Master.
The U.S. Naval Observatory (USNO) monitors the timing of the Global Positioning System (GPS) to
provide a reliable and stable coordinated time reference for the satellite navigation system. GPS time is
automatically steered to UTC(USNO) on a daily basis to keep system time within one microsecond of
UTC(USNO). However, after processing the timestamps from the GPS Antenna/Receiver, the AllSync
Master maintains the time within approximately one second of UTC.
Once configured with the GPS option and properly enabled, the AllSync Master automatically updates its
timekeeping to the GPS receiver once per hour (on the 4th minute of each hour). Manual synchronization
can also be performed, by using the ADJ key on the AllSync Master (refer to the AllSync Master Operation
Manual).
Glossary
Specifications
Troubleshooting
Installation
Introduction
The GPS Option for the AllSync Master provides two main benefits:
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AllSync GPS Option
User Manual
Installation
The following are requirements for installation of the GPS Option for the AllSync Master:
Troubleshooting
Figure 1 (page 6) is an exploded view diagram showing the various components in the GPS kit, in this case
for a mast installation. Refer to the part numbers in the included table for reference.
Installation
1.AllSync Master(s) configured with the GPS option, and with GPS communication enabled (models
ASMA00G, ASMA02G, ASMA04G, ASMA06G, ASMA00M, ASMA02M, ASMA04M, and
ASMA06M)
2.GPS kit, part # H000817, including:
a.Part # H0004381 - GPS Smart Antenna/Receiver
b.Part # H001202A - GPS Cable - 50 foot
c.Part # H006214 - Shrink tubing for water-tight connections
d.Part # H000835 - GPS Antenna mounting bracket
3.For Mast Installation, Pipe, Tubing, or other cylindrical object for use as an antenna mast (not included
with GPS kit - to be furnished by customer or installer), along with necessary mounting hardware to fix
the mast to the building or other structure
4.GPS Extension cable(s), if needed - each 50 foot, part # H000818
Introduction
Requirements
Specifications
Glossary
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Introduction
Installation
AllSync GPS Option
User Manual
Figure 1 - GPS Kit Exploded View
Installation
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6
8
7
3
5
4
Specifications
Troubleshooting
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Glossary
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6
ITEM NO.
1
2
3
4
5
6
PART NUMBER
H004381-1
H004381-2
H000835-2
H000835-3
H000835-4
H000834-2
Description
Bracket-GPS Antenna Mount 28 mm hole
GPS Smart Antenna-Synergy Systems 10001510
Pipe, not supplied with kit
U-bolt, 1/4-20 supplied in kit
Nut, GPS-supplied in kit
Washer, Rubber spacer
QTY.
1
1
1
2
1
1
7
H000835-5
Lock Washer, 1/4
4
8
9
H000835-6
H001202A
Hex Nut, 1/4-20
50 ft. cable
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AllSync GPS Option
User Manual
Installation
Follow these steps to mount the GPS antenna
Troubleshooting
Specifications
Glossary
© American Time
Installation
1.Determine a suitable location
a.The GPS Antenna with integrated receiver is designed for outdoor installation, in a location with a full
view of the sky. For best results attach the antenna to an outside wall or to a mast on a roof.
b.It is best to pick a location unobstructed by trees, branches, power lines, other buildings, etc.
However, only one satellite is required to be in view of this antenna to obtain a valid timestamp*, so it
may be possible to locate the antenna in an area with a limited view of the sky. If you wish to mount
the GPS antenna in a location with a limited view of the sky, it is recommended that you test the GPS
functionality before permanently affixing the antenna in this location. *NOTE: At least three satellites
are required for fixing a position, for the purposes of computing LMT (Local Mean Time).
c.While not ideal locations, skylights or windowsills may be possible options for installation. However,
note that the GPS signal has difficulty penetrating the metal oxide coating of Low-Emissivity glass
(known as Low-E glass), so avoid installation behind such glass. Also keep in mind that snow, ice, or
debris may at times cover some skylights or obscure the view from windows.
d.Avoid installing the GPS antenna in locations near high power transmitting antennas. The receiver
is designed to filter out unwanted frequencies, but avoiding locations near transmitting antennas is
prudent to avoid possible harmonics that may be within the passband of the Antenna/Receiver.
e.To avoid lightning strikes, it is recommended that the GPS Antenna be installed in an area where it is
not at the highest point, and so that any lightning rods are well above the antenna. The GPS Antenna
is not designed to withstand a direct hit from lightning, although it has protection to survive the
secondary effects of lightning.
f. The GPS antenna is environmentally sealed and able to withstand harsh climates. However, if installing
in climates where significant snowfall is possible, mount the GPS Antenna high enough so it does not get
buried by snow or ice, which may cause damage to the unit or impede the GPS signal.
2.Fix the anodized aluminum mounting bracket (item No. 3 in Figure 1) to the building or antenna mast:
a.If using a mast, it should be made from 1" schedule 40 pipe, or any rigid tubing or conduit with
an outside diameter of 1.5" or less. Using the U-bolt, hex nuts and lock washers supplied with the
mounting bracket, fix the bracket to the mast (see Figure 1). NOTE: The Mast must be grounded.
b.If attaching the mounting bracket directly to a structure (wall, roof, or other fixed structure), select
proper fasteners and washers to securely fix the bracket.
3.Unthread and remove the nut (item No. 7 in Figure 1) from the GPS Antenna.
4.Take the GPS Antenna (item No. 1 in Figure 1) with rubber washer (item No. 8 in Figure 1) and place
on top of the mounting bracket, feeding the antenna cable through the hole in the mounting bracket.
5.Secure the GPS Antenna to the mounting bracket using the nut (item No. 7 in Figure 1) you removed in
step #3.
6.Route the 15-meter (approx. 50 ft) cable (item No. 9 in Figure 1) from the GPS antenna to the AllSync
Master. Use cable ties or other suitable method(s) to secure the cable.
Introduction
Mounting the GPS Antenna
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AllSync GPS Option
User Manual
7.Before connecting the cable to the GPS antenna, feed the shrink tubing (item No. 9 in Figure 1) around
the end of the cable.
8.Make the connection from the 15-meter cable to the GPS Antenna - the 12-pin connectors are keyed so
they align properly. The male 12-pin connector of the GPS Antenna should mate to the female 12-pin
connector of the 15-meter cable. Complete the connection with a clockwise twist of the connector sleeves,
which locks the cables together.
9.Slide the shrink tubing in place so it is centered over the connectors and use a heat gun to shrink the
tubing around the connection, making it watertight. You may wish to wait until the GPS function is
tested OK before completing this step.
10.If the 15-meter cable is not long enough to reach from the AllSync Master to the GPS antenna, procure
15-meter extension cables (American Time & Signal Co. part # H000818) and locate them between the
cable provided with the GPS kit and the AllSync Master. NOTE: The cable that comes with the GPS kit
should always be installed to the GPS antenna. The total length of all cables should not exceed 1500 feet,
or 30 standard cable lengths.
Connecting the AllSync Master
Once you have routed the cable to the AllSync Master, make the connection from the female 12-pin
connector on the cable (from the GPS antenna) to the male 12-pin port on the AllSync Master. The GPS
port is the middle socket on the left side.
Glossary
Specifications
Troubleshooting
Installation
Introduction
Installation
GPS cable installed to GPS port on AllSync Master
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AllSync GPS Option
User Manual
Installation
Installation
Troubleshooting
Specifications
Once you have the GPS hardware installed, the GPS feature should function. Perform the following steps to
ensure the feature is working properly.
1.After installation, verify the GPS function is enabled. On the AllSync Master, press PROG, 5, 2, XXXX
(user code), and 1. Then press BACK to exit the GPS menu. At this point the BACK key brings you to
the main time screen in present version.
2.Now verify the signal status. On the AllSync Master, press PROG, 5, 1, OK. You should then be able to
view the last timestamp received (if applicable) and the number of satellites in view, as reported from the
GPS Antenna/Receiver. Press OK, OK, and BACK to exit the GPS menu. If no satellites are reported in
view, follow the troubleshooting instructions.
3.Now adjust the time via GPS: On the AllSync Master, press ADJ. The unit should display, “2=GPS Sync
Now.” NOTE: If it shows anything else, change the Time Sync Priority by pressing BACK, PROG, 7,
XXXX (user code), OK, 3. Now you should select option 1 for GPS. Use the BACK key to exit to the
main screen and press ADJ.
4.Press 2 to sync the time to GPS. The unit will respond with a message confirming the sync was successful,
and the time should automatically set. NOTE: You may have to wait for up to 25 minutes for the time to
sync accurately to UTC time (NIST) since the initial GPS time received will not account for leap seconds.
This is a nature of the GPS message - the current leap second difference from GPS time is only broadcast
once in a 12.5 minute Navigation message. As of December 31,2008, GPS time is ahead of UTC by 15
seconds. Therefore, until the leap second correction is received, the AllSync Master will report the time
15 seconds ahead of UTC time.
5.The unit is now configured and will update the internal clock of the AllSync Master every hour, on the
4th minute, or whenever the ADJ function is used to force an update.
Introduction
Configuring the AllSync Master
Glossary
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Troubleshooting
AllSync GPS Option
User Manual
1.If GPS antenna has been connected to the AllSync Master for less than 25 minutes, the GPS time signal
may be inaccurate. Allow more time and try again.
2.Check GPS cable connections between master and GPS antenna. Replace any damaged cables and verify
the connectors are securely locked together.
3.If no signal has been received after checking the status and configuration, move the GPS antenna to a
better location and follow the installation and configuration steps again.
4.Ensure the GPS update function is enabled (step #1 under “Configuring the AllSync Manager”)
5.Inspect the GPS Antenna for damage. Look for signs of lightning strikes or falling debris.
6.Look for obstructions to the Antenna’s view of the sky and remove them if possible (example: tree
branches). Clear any snow or ice off the GPS Antenna and surrounding areas.
7.If the GPS Antenna is installed behind a Low-E glass window or skylight, try another location or replace
the glass if possible.
If the problem cannot be resolved after following these steps, please call Technical Support at American
Time & Signal Co. at 1-800-328-8996.
Glossary
Specifications
Troubleshooting
Installation
Introduction
If you have trouble synchronizing to GPS, follow these troubleshooting steps:
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AllSync GPS Option
User Manual
Specifications
Physical Characteristics
Size....................................................... 4" deep x 3" high (102mm x 76 mm)
Weight.................................................. 14 oz. (0.4 kg)
Housing Material.................................. Cycolac ABS Radome, Aluminum base
Pigtail cord............................................ Approx. 20” (0.5 m)
Environmental Conditions
Specifications
Operating Temp................................... -40ºF to +167ºF (-40ºC to +75ºC)
Storage Temp........................................ -40ºF to +185ºF (-40ºC to +85ºC)
Relative Humidity................................. 85% non-condensing at -22ºF to +140ºF (-30ºC to +60ºC)
Troubleshooting
Extension Cable Connectors:................Deutsch MMP21-2212S1 (12-pin Male; 12-pin Female)
Antenna Connector...............................Binder M16-423 (12-pin Male)
Mating Connector................................Binder M16-423 (12-pin Female)
Power Specification............................... +9v to +30vdc, 70mA Max
Power supplied...................................... +13.6vdc
Max. Extension Cable Length............... 1500 ft (457 m)
Communication.................................... RS-422
Installation
Electrical Interface
Introduction
GPS Antenna/Receiver Specifications
Glossary
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Glossary
Specifications
Troubleshooting
Installation
Introduction
Glossary of Terms
AllSync GPS Option
User Manual
GPS - Global Positioning System, a constellation of satellites operated by the United States Military (US
Naval Observatory) that broadcast precisely timed signals from space. These signals are used for extremely
accurate global navigation as well as the distribution of precise time.
Leap Second - A second of time as measured by an atomic clock, added to or omitted from official
timekeeping systems annually to compensate for changes in the rotation of the earth.
LMT - Local Mean Time, the Mean Solar Time for any given longitude around the earth. It differs at every
longitude (1 hour change for every 15 degrees longitude). LMT may or may not correspond with the local
time in a given time zone.
Low-E glass - Low Emissivity Glass - this type of glass features a unique surface coating that reduces the
heat transfer through the window. Such a coating can reflect anywhere from 40% to 70% of the normally
transmitted heat, while not inhibiting the amount of light that passes through the window. However, the
metal oxide coating of Low-E glass does not allow the GPS signals to pass through. Thus, mounting the
GPS antenna inside a window with Low-E glass is not recommended.
NIST - National Institute of Standards and Technology - The Time and Frequency Division, part of
NIST’s Physics Laboratory, maintains the standard for frequency and time interval for the United States
and provides official time to the United States. This includes traceability from the GPS timing signals to the
NIST national frequency standard.
RS-422 - Standard communications interface approved by the Electronic Industries Alliance (EIA) for
connecting serial devices and supporting multi-point connections. This interface supports higher data rates
and a higher immunity from interference than RS-232 and is used for the communication between the
AllSync Master and the GPS receiver.
Shrink Tubing - Tubing which has been extruded, cross linked, and mechanically expanded which,
when reheated, will return to its original diameter. For this GPS kit, it is used to protect the electrical and
communications connections from water, etc. It can be easily installed over the connectors and will shrink
tightly over them after being heated.
Synchronization - The process of bringing 2 clocks or time sources into phase so their difference is zero.
In the case of a timekeeping system, time synchronization takes place between the master clock and all
secondary clocks. In addition, in the case of the GPS timekeeping option, the master clock (AllSync Master)
is synchronized to the GPS time source so the time output of the master is matched to the NIST time
standard.
Timestamp - A time mark or notation that indicates the date and the time.
Navigation Message - A message, transmitted by each GPS satellite, containing its orbital elements, clock
behavior, system time and status messages.
USNO - The U.S. Naval Observatory - a organization within the United States Navy which determines
precise time and maintains the Master Clock for the United States. The USNO monitors the timing of the
Global Positioning System (GPS) to provide a reliable and stable coordinated time reference for the GPS
satellite navigation system.
UTC - Universal Coordinated Time - A time-scale that forms the basis of a coordinated distribution of
standard frequencies and time signals throughout the world. It is often referred to as Greenwich Mean Time
(GMT) or Zulu Time (military and aviation).
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Introduction
Installation
Troubleshooting
Specifications
Glossary
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User Notes
AllSync GPS Option
User Manual